1. Technical Field
This disclosure relates generally to pumps and more particularly to an arrangement for locating an outer pump casing and inner pump liner relative to one another.
2. Background Art
Pumps of the centrifugal type generally comprise a pump housing the interior of which forms a pump chamber. An impeller is positioned in the pump chamber and is connected to a drive shaft and drive motor that impart rotation to the impeller. The pump housing is formed with an inlet for receiving pumped material into the pump chamber, and a discharge outlet through which pumped material exits the pump chamber.
The pump housing typically comprises an outer casing comprising two casing halves that are joined together to form the pump housing. The two halves may comprise a suction side, corresponding to the wet end of the pump or the side at which the pump inlet is located, and a drive side, through which the drive shaft and shaft seals are positioned. The suction side casing and drive side casing are typically joined about a peripheral edge that lies in a plane perpendicular to the rotational axis of the pump.
Such pumps may include an inner liner that is positioned within the pump casing to protect the interior surface of the pump casing or pump chamber from damaged caused by abrasive particles in a slurry that is being processed by the pump. The inner liner may be made of an elastomeric material that is abrasion resistant or may be made of metal. The inner liner may be one piece or similar to pump casings, be made of two halves that are joined about a peripheral edge that is formed in a plane perpendicular to the rotational axis of the pump. In conventional arrangements, the two inner liner parts are secured together about the periphery by having an outwardly extending flange that is held between the peripheral edges of the two casing halves and bolted in place.
In conventional centrifugal pump embodiments as described, the inner liner is further attached to the drive side of the casing by a plurality of bolts that extend through the drive side pump casing and engage the inner liner that is positioned adjacent the interior surface of the drive side casing about a central opening provided for extension of the drive shaft therethrough. Problems can occur with the described means of attaching the inner liner to the pump casing, such as failure of the bolts or screws to adequately secure the inner liner to the casing.